What he has, makes him what he is (5)
I believe the answer is:
owner
This clue might be a double definition.
'what he has' is the first definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'him what he is' is the second definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'makes' is the link.
Can you help me to learn more?
(Other definitions for owner that I've seen before include "Person with legal title to something" , "Legal possessor" , "The one in lawful possession" , "Holder, possessor" , "The person in legal possession" .)